Label inspection slitter/rewinder

ABSTRACT

This invention provides a web processing device which has an unwinding mandrel and a rewinding mandrel, and is adapted to receive rolls of web on the former and rewind the web on the latter. Between the mandrels, the unwinding web is made to follow a path which brings it sequentially to a web inspection location and a splicing location. Braking means are provided for halting the movement of the web along the path. The distance along the path between the web inspection location and the splicing location is long enough to permit the braking means to halt the movement of the web before a given point on the web can move the full distance from the web inspection location to the splicing location. In this way, there is no need to provide reverse drive facility on the unwinding mandrel for the purpose of moving the web backwards should a faulty section detected at the inspection location over-shoot the splicing location.

y 3 A. R. PRITTIE 3,733,230

LABEL INSPECTION SLITTER/REWINDER Filed Feb. 8, 1972 .3 Sheets-Sheet l FIG. 1

y 15, 1973 A. R. PRITTIE 3,733,230

LABEL INSPECTT ON SLIT'IER/RILWINDFIR Filed Feb. 8, 1972 Sheets-Sheet 1- 56 A eso fi| giz 3/ D E United States Patent 3,733,230 LABEL INSPECTION SLITTER/REWINDER Allan R. Prittie, 12 Blackdown Cr., Islington, Ontario, Canada Filed Feb. 8, 1972, Ser. No. 224,427 Int. Cl. B65h 17/34 US. Cl. 156-64 8 Claims ABSTRACT OF THE DISCLOSURE This invention provides a web processing device which has an unwinding mandrel and a rewinding mandrel, and is adapted to receive rolls of web on the former and rewind the web on the latter. Between the mandrels, the unwinding web is made to follow a path which brings it sequentially to a web inspection location and a splicing location. Braking means are provided for halting the movement of the web along the path. The distance along the path between the web inspection location and the splicing location is long enough to permit the braking means to halt the movement of the web before a given point on the web can move the full distance from the web inspection location to the splicing location. In this way, there is no need to provide reverse drive facility on the unwinding mandrel for the purpose of moving the web backwards should a faulty section detected at the inspection location over-shoot the splicing location.

This invention relates generally to web-processing apparatus, of the kind adapted to perform certain operations on a roll of web unreeling from a mandrel. More particularly this invention relates to web-processing apparatus in which the web may be continuously inspected for faults, and in which any faults can be spliced out at a splicing location.

GENERAL BACKGROUND OF THE INVENTION -In recent years, it has been the practice for manufacturers of labels, tabs and tags to receive from a label Stock Manufacturer rolls of label stock (hereinafter called web) and to perform operations on these rolls such as printing, die-cutting etc. These rolls, which may or may not include a supporting liner which transports the labels, can be up to 24 inches in diameter (or sometimes more), and from 8 to 13 inches in web width. The labels, etc. can be arranged either in contiguous or in spaced relation to one another. Depending upon the size of each label, there may be anywhere from 1 to 15 labels across the width of the web.

Because the rolls of webas initially produced by the label manufacturer are unsuited for certain types of end requirements, an intermediate operation is necessary, in which the large, bulky rolls are rewound into smallerdiameter rolls and slit lengthwise into narrower web widths if the nature of the labels makes it desirable. Also, the large-size rolls of labels often have flaws and defects which must be spliced out.

Furthermore, because the label manufacturer has only an approximate idea of the total number of labels in one of his large-diameter rolls, it is sometimes desirable to rewind the web so that a more accurate count can be made. In some applications, such as those involving pharmaceutical labels, it is necessary to have an absolutely accurate count of the number of labels in a roll, or otherwise the roll will be rejected. The rolls of labels are purchased on condition that the stated number of labels in each roll be exactly correct. This latter situation arises, for example, where a pharmaceutical company is bottling medicine. The bottling, labelling and sealing apparatus in the pharmaceutical bottling plant is such that it must be fed with a controlled number of bottles,

a controlled number of labels, and a precisely measured amount of medicine, so that when all of these are wedded together, any remainder can be accurately predicted and verified.

In order to do precise counting, a digital counter is provided in conventional machines.

DRAWBACKS OF THE PRIOR ART Many conventional web splicer/slitter/rewinders pass the web from the unwinding roll through a splicing location, and then to an inspection location, a slitter, and finally to the rewind mandrel or mandrels. The inspection location is situated anywhere between the splicing location and the rewind mandrel but invariably coincides with or follows the splicing location in presently-available machines.

Be cause of this arrangement, the detection of a fault or a defect in the web requires that the movement of the web be stopped and then reversed, in order to bring the defective portion back to the splicing location. This requirement for reversed movement of the web makes it necessary to provide a reverse drive for the unwind mandrel in addition to the braking apparatus for that mandrel.

Also, under certain circumstances where precise digital counting of the labels in the roll is required, a halting and reverse movement of the web can lead to an erroneous count for reasons that will be explained later with reference to the drawings.

OBJECTS OF THIS INVENTION In view of the above disadvantages of the presentlyavailable machines for slitting, splicing and rewinding rolls of web, it is an object of this invention to provide a web-processing apparatus so arranged and constructed that it does not require a reverse-movement capability. The elimination of the need for reverse-movement of the web obviates the necessity for providing positive reverse drive to the unwind mandrel, and braking to the rewind mandrel, obviates the need for a reversible counter, and totally eliminates the risk of mis-counting.

GENERAL DESCRIPTION OF THE INVENTION Accordingly, this invention provides a web-processing device, comprising: an unwinding mandrel adapted to unwind a roll of web, a rewinding mandrel, means adapted to guide a web along a path from said unwinding mandrel to said rewinding mandrel, braking means for halting the movement of the web along said path, a web inspection location in said path, and a splicing location in said path between said web inspection location and said rewinding mandrel. The distance between the web inspection location and the splicing location is at least as long as the maximum length of web to be unreeled from the roll during the operation of the means for halting the movement of the web, whereby the web defects detected at the inspection station can be arrested upstream of the splicing location through the action of said means.

GENERAL DESCRIPTION OF THE DRAWINGS One embodiment of this invention is illustrated in the accompanying drawings, in which like numerals denote like parts throughout the several views, and in which:

FIG. 1 is a perspective view of an apparatus for processing a roll of web, embodying this invention;

FIG. 2 is a schematic illustration of the components of an apparatus embodying the invention;

FIGS. 3 and 4 are elevational views of a web illustrating the way in which reverse web movement can lead to erroneous digital counting.

3 DETAILED DESCRIPTION OF THE DRAWINGS Attention is directed first to FIG. 1, which shows a web-processing apparatus which includes a main frame and housing 12 steadied by two leg braces 14.

An unwinding mandrel )16 extends horizontally outwardly from the housing 12 in the lower portion thereof. The unwinding mandrel 16 is preferably of the conventional expanding type, and is adapted to receive and grip a roll 18 of web 19.

The web 19, as it unreels from the roll 18, passes initially over a first idler roller 20 mounted on the housing 12 generally above the roll 18. The web 19 is then directed horizontally to the right and passes around a second idler roller 22 supported at the end of a brace element 24.

The web 19 then passes obliquely downwardly and is entrained around a third idler roller 25, from which it passes to a fourth idler roller 26, and thence to edge guide roller 28 which is provided with two flanges 29 between which the web 19 can be entrained. The edge guide roller 28 is supported at the left end of the brace element 24. After the edge guide roller 28, the web 19 passes rightwardly to a fifth idler roller 30, from which it enters the nip between a draw roll 32 and a nip roll (not shown in FIG. 1 but visible at 33 in FIG. 2).

After passing between the draw roll 32 and the nip roll 33, the web 19 passes between a pair of rotary shearcut slitters 35, thence around a sixth idler roller 36, and finally around a rewinding mandrel 38.

A uni-directional digital counter 40 is provided atop the housing 12, but may be incorporated into the housing if desired. The sensing head which controls the counter, of conventional construction, is located within an auxiliary housing 42, but may be located at any position between the fifth idler roller 30 and the rewinding mandrel 38.

A conventional control panel 44 is also mounted on the housing 12, but need not be described in detail here.

Between the roll 18 and the roller 28, at an area marked generally with the number 46, is a web inspection location at which the moving web 19 can be examined either by an operator who simply monitors the web 19 as it passes, or by automatic or semi-automatic web-inspection means, of conventional nature, using for example a stroboscopic device 48. In the embodiment shown, an ordinary electric lamp 50 is also provided at the web inspection location 46.

After the web 19 has passed the idler rollers 22, 25, 26 and the edge guide roller 28, it comes to a splicing location shown generally at 62.

The splicing location 52 includes two bar clamps 54 of conventional construction. At the splicing location 52, the web 19 is adapted to pass over the surface of a horizontal table 55 supported by the brace element 24, and against which the bar clamps 54 are adapted to clamp the web 19. In order to remove a section of defective web, the web is first clamped using the right clamp 54, and then cut laterally with a knife (not shown) which is guided in a splice guide tract (not shown). The defective web is then pulled forward until the section of defective material has gone past the edge already cut. Then, the lateral edges of the two pieces of web are lined up and the upstream section of web is locked with the left clamp 54. The knife is then again used to cut the upstream section of web in the same splice guide track, and the two pieces of web are then spliced together using tape (not shown). The foregoing splicing procedure is conventional, as are the different devices used to carry it out, and none of these need to be described in detail in this disclosure.

The preferred embodiment of this invention contemplates that the distance along the web between the web inspection location 46 and the splicing location 52 be at least as long as the maximum length of web unreeling from the roll 18 during the operation of the braking means to halt the movement of the web. This gives an operator sufficient time, after he detects a fault in the web, to bring the web to a stand-still before the fault reaches the splicing location. This means that the operator is not required to reverse the machine to retrieve defective web from the rewinding mandrel or from a location downstream of the splicing station. This means that slit side-register problems caused by reversing are avoided. It also obviates the need for a bi-directional counter and totally eliminates the risk of erroneous digital counting which arises whenever re verse web movement is utilised.

The manner in which this erroneous counting arises will now be explained with referennce to FIGS. 3 and 4.

In FIG. 3 the web 19 is shown in elevation so that it appears in edge view. The web 19 includes a liner 57 which has adhered to its upper surface a plurality of sequential labels A, B, C, D, etc. Two components of the counting head are shown in FIG. 3, the first being a light source 56 adapted to throw a parallel pencil of light downwardly at right angles to the web 19, the second being a photo electric cell 58 placed beneath the web 19 directly in the path of the pencil of light being emitted from the light source 56. The liner '57 is relatively transparent to the light being emitted from the light source 56, while the labels A, B, C, D, etc. are relatively opaque. It will be noticed that the labels A, B, C, etc. are slightly spaced from one another in the longitudinal direction. Let us assume that the digital counter is set so that it counts one" each time the light level received by the photoelectric cell '58 passes from high to low (or light to dark). If we assume that the web 19 is moving to the right, then the last added unit in the digital counter will have taken place when the leading edge 60 of label B passed across the pencil of light from the source 56. The unit prior to that was added when the leading edge 62 of label C cut through the pencil of light, and so forth. The digital counter ignores the change from low level to high level as the trailing edge of each label passes between the light source 56 and the photoelectric cell 58.

Now let us consider what happens when a fault in the web is detected by the operator, and he brings the web to a halt. We are dealing now with the prior art sequence, in which it is necessary to move the web 19 backwards along its track so that the defective section of web can be brought to the splicing location. Because the labels have a greater dimension in the longitudinal direction than the gaps between them, the chances are that the 'web will come to a halt with a label stationary between the light source 56 and the photoelectric cell 58, exactly as shown in FIG. 3. We will here assume that the last unit added by the digital counter when the leading edge 60 passed across the pencil of light brought the total to 1004. Now, when the web direction is reversed and the web 19 begins to move to the left in FIG. 3, the digital counter is instructed to subtract one unit from the total each time the protoelectric cell 58 passes from high level to low level. Let us assume that the web moves left-wardly a distance equal to twice the width of a label, and comes to a halt with the label D situated between the light source 56 and the photoelectric cell 58. In moving backwards, the digital counter would have subtracted one as the leftward edge 64 of the label C passed across the pencil of light, and would have subtracted one more as the leftward edge 66 of the label D passed across the pencil of light, taking the total down to 1002. After removal of the defective portion of the web, forward motion (to the right) would begin again, and the digital counter would correctl register label C at 1003, label B as 1004, label A as 1005, etc. In the case just described, therefore, no error in the digital counting would result.

However, consider the case when the initial halting of the web occurs with the light source 56 directly above a gap between two adjacent but spaced labels. This situation is shown in FIG. 4. The pencil of light has not yet been cut by the leading edge 60 of the label b, and thus the last-counted label was label C, which numbered 1003.

Suppose now that the reversal of web movement takes place, and comes to a halt with the label D lying directly between the light source 56 and the photoelectric cell 58. The digital counter would have subtracted one for the leftward edge 64 of the label C, and one more for the leftward edge 66 of the label D, taking the total down to 1001. After the splicing, when the rightward motion of the web 19 recommences, the digital counter will count label C 1002, label B 1003, and so forth, which is incorrect by one unit. The error arises because one of the halts of the web found an inter-label gap at the pencil of light, while the other halt found a label blocking the pencil of light.

It is now seen that, where absolute correctness in counting is a requisite, the reverse web movement must be eliminated, at least when the counting utilises a gapdetecting process similar to that described above.

Passing the unreeling web along a path which encircles the roll 18 is one way of ensuring a sufficient length of web between the web inspection location 46 and the splicing location 52 to permit the braking means 68 (shown in broken lines in FIG. 2) to halt the rotation of the roll 18 before the detected faulty section of the web 19 reaches the splicing location 52. After the initial halt, the web is then moved forward slowly (not backward) until it reaches the splicing station 52.

It will be understood that the braking means 68 could be replaced by some other web-halting means not necessarily acting on the unwinding mandrel 16.

What I claim is:

1. A web-processing device, comprising:

an unwinding mandrel adapted to unwind a roll of web,

a rewinding mandrel,

means adapted to guide the web along a path from said unwinding mandrel to said rewinding mandrel, braking means for halting the movement of the web along said path,

a web inspection location in paid path,

a splicing location in said path between said web inspection location and said rewinding mandrel,

the distance along the web between the web inspection location and the splicing location being at least as long as the maximum length of web unreeling from said roll during the operation of said means to halt the movement of said web, whereby a web fault detected at said inspection location can be arrested upstream of the splicing location through the action of said means.

2. The invention claimed in claim 1, which further includes a nip-roller station in said path between the splicing location and the rewinding mandrel, the web undergoing a change in tension at said nip-roller station.

3. The invention claimed in claim 1, in which the said path encircles the unwinding mandrel and is spaced sulfi- 6 ciently far therefrom to avoid contact with a roll of web mounted thereon.

4. The invention claimed in claim 1, which further includes uni-directional counting means between the splicing location and the rewinding mandrel, adapted to count sequential discrete lamina elements of the web.

5. The invention claimed in claim 1, which further includes a nip-roller station in said path between the splicing location and the rewinding mandrel, the web undergoing a change in tension at said nip-roller station, said path encircling the unwinding mandrel and being spaced sufiiciently far therefrom to avoid contact with a roll of web mounted thereon, the web-processing device further including uni-directional counting means adapted to count sequential discrete laminar elements of the web.

6. A method of processing a roll of web, comprising:

unwinding the roll of web from an unwinding mandrel,

passing the web along a path which brings it sequentially to (a) a web inspection location, (b) a splicing location, and (c) a rewinding mandrel,

inspecting the web at said web inspection location,

upon the detection of a flaw in the web, halting the movement of the web before the flaw reaches the splicing station,

advancing the web until the flaw reaches the splicing station,

and splicing out the flaw.

7. The method claimed in claim 6, in which the path distance between the web inspection location and the splicing location is at least as long as the maximum length of web unreeling from said roll during the operation of said means to halt the movement of said web.

8. The invention claimed in claim 7, which includes the step of counting sequential discrete laminar elements of said web at a location between the splicing location and the rewinding mandrel.

References Cited UNITED STATES PATENTS 3,024,157 3/1962 Beerli 24258.1 X 2,581,711 1/1952 Roselius 24258.1 2,998,204 8/1961 Walsh 24258.1 3,567,534 3/1971 Kushiro 156 6.1 3,547,170 12/1970 Maxey et al. l56-98 X EDWARD G. WHIT BY, Primary Examiner US. Cl. X.R. 

